End structure of middle grid section of sintering machine trolley
By optimizing the end structure of the grate bar in the sintering machine, increasing the width and designing the heat dissipation cavity, the problems of thermal deformation and rapid burning of the end of the grate bar are solved, extending the service life and improving production efficiency.
Patent Information
- Application Number
- CN202421693806.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-17
- Publication Date
- 2025-06-20
- Estimated Expiration
- 2034-07-17
AI Technical Summary
After the sintering process technology is improved, the service life of the existing sintering machine grate bars has been shortened. The main reason is that the thermal accumulation at the end cannot effectively dissipate heat, resulting in rapid thermal deformation and oxidation burning.
By optimizing the end structure of the grate bar, increasing width, designing the cavity for heat dissipation, strengthening the ribs to enhance rigidity, and providing limit grooves and bosses at the ends to control relative displacement, an asymmetric structure is formed to achieve self-cleaning performance.
It effectively solves the problems of thermal deformation and rapid burning at the end of the grate bar, extends the service life, reduces the oxidation burning speed, improves production efficiency, and reduces manual replacement and spare parts loss.
Smart Images
Figure CN223005314U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to spare parts of a sintering machine trolley for iron ore sintering production, and specifically relates to an end structure of grate bars in the middle of a sintering machine trolley. Background Art
[0002] A sintering machine trolley is used to carry a mixture of iron ore, flux and fuel. After high-temperature ignition and under the action of induced draft, it completes the sintering of iron ore into sinter cakes. During the production process, the sintering machine trolley moves in a caterpillar track, undertaking sintering steps such as loading, ignition, sintering and unloading, and repeating the operation in a cycle. Grate bars are important components of the sintering machine trolley, neatly arranged on the bottom cross beam of the sintering machine trolley, in a grid shape, generally arranged in 2 to 3 rows in the width direction of the trolley.
[0003] The grate bars mainly play the following roles during sintering: one is to carry the sintering material and keep it running, and the other is that the gaps between the grate bars are used to form the air ducts for sintering induced draft, bearing the erosion and corrosion of high-temperature waste gas, dust, water vapor and other media. At present, the existing grate bars in sintering machines are all single grate bars, that is, each end of a grate body is respectively provided with an upper wing and a lower wing, and both ends are symmetrically shaped. The overall shape is long strip-shaped, and the length, width and height are generally (320 - 495) × (25 - 40) × (120 - 150) mm. The material is generally high-chromium cast iron. This kind of grate bar can adapt to the working conditions where the sintering material layer is less than 800 mm and the sintering end temperature is less than 350 °C, and the service life is generally 2 - 3 years.
[0004] With the progress of sintering process technology, the sintering material layer generally reaches more than 900 mm, and even up to 1030 mm, and the sintering end temperature generally exceeds 400 °C. The above-mentioned sintering process will shorten the service life of the grate bars to about 1 year. The main reason for its failure is the bending deformation and fast burning loss speed (becoming thinner) at the ends of the grate bars. According to statistics, the failure of the ends of the grate bars accounts for more than 86% of the total failed grate bars. The main reason is that thermal accumulation will occur at both ends of the grate bars, and effective heat dissipation cannot be achieved, resulting in the working temperature reaching 900 - 1300 °C, which is 170 - 320 °C higher than that in the middle of the grate bars, exceeding the maximum heat-resistant temperature (700 - 950 °C) of the high-chromium cast iron material. Moreover, since the width of the end is 30 - 45 mm, under the high-temperature working conditions during sintering, the ends of the grate bars are extremely easy to deform. After deformation, the contact area with the hot waste gas increases, accelerating its oxidation and burning loss speed.
[0005] At present, domestic sintering machines have basically achieved large-scale and automation, and there are very few on-site employees. Due to the short service life of conventional grate bars, a large amount of replacement is required during the scheduled maintenance of the sintering machine, which is time-consuming and laborious. Replacing the grate bars has become a long-term task during the scheduled maintenance of the sintering machine, and also increases the production cost of the enterprise.
[0006] In summary, how to improve the structure of the grate bars to effectively ensure the service life and performance of the grate bars while adapting to the improvement of sintering process technology is a technical problem to be solved. Summary of the Invention
[0007] In view of the deficiencies of the prior art, the present invention provides an end structure of the middle grate bars of a sintering machine trolley. By optimizing the shape of the end structure, the problems of deformation, creep, and rapid burnout at both ends of the middle grate bars are effectively solved, the normal air passing volume (constant air extraction area) is maintained, the production efficiency is improved, the manual replacement workload and spare part loss are reduced, and the smooth progress of production and scheduled maintenance is ensured.
[0008] The technical solution of the present invention is as follows: An end structure of the middle grate bars of a sintering machine trolley, including a grate body, with ends provided at both ends of the grate body, and the width L of the ends is not less than 45 mm.
[0009] Preferably, the grate body can be at least two, and a 5 - 10 mm air passing gap is formed between adjacent grate bodies.
[0010] Preferably, the upper wing and the lower wing are in contact with the trolley crossbeam, and a cavity for heat dissipation is provided at the contact position between the upper wing and the trolley crossbeam.
[0011] Preferably, it further includes a reinforcing rib, and the reinforcing rib is located inside the cavity and abuts against the inner wall of the cavity.
[0012] Preferably, a limiting groove is provided on one side of the end, and a limiting boss is provided on the other side.
[0013] Preferably, a 30 - 70° inclined surface is provided on the upper surface of the end of the grate bar.
[0014] Preferably, when the grate body is two, it can be divided into grate body one without a lower wing and grate body two with a lower wing, and grate body one and grate body two are connected by a cross - bridge.
[0015] Preferably, grate body one and the end form a sub - grate bar, and grate body two, the end, and the lower wing form a mother - grate bar. The sub - grate bar and the mother - grate bar are of an asymmetric structure and the weight of the mother - grate bar is greater than that of the sub - grate bar.
[0016] The beneficial effects of the end structure of the grate bars provided by the present invention are as follows: By increasing the width at the end position, the situation that the ends of the grate bars are extremely prone to deformation under the high - temperature working conditions during the sintering process can be effectively solved, the oxidation burnout speed is reduced. Compared with single - body grate bars, the cold and hot rigidity is significantly increased, the problems of creep and rapid burnout at the ends of the grate bars are solved, the service life of the grate bars is extended, the manual replacement and spare part loss are reduced, the production efficiency is improved, and the production cost of the enterprise is reduced.
[0017] And it is convenient for manual replacement; the asymmetric structural features have the performance of online self-cleaning and can also ensure the normal ventilation volume of sintering production; it can be smoothly replaced and installed without modifying the existing trolley body. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 is the front view of the grate bar end structure of the present utility model;
[0019] Figure 2 is Figure 1 the side view of
[0020] Figure 3 is Figure 1 the top view of
[0021] Figure 4 is Figure 1 the A-A cross-sectional view of
[0022] Figure 5 is Figure 3 the B-B cross-sectional view of
[0023] Reference numerals: 1, grate body; 1-1, grate body one; 1-2, grate body two; 3, lower wing; 4, end; 5, upper wing; 7, trolley cross beam; 8, mother grate bar; 9, son grate bar; 10, limiting groove; 11, limiting boss; 12, mother-son cross bridge; 13, inclined surface; 14, reinforcing rib; 15, cavity. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0024] As shown in the figure, the grate bar end structure of the present utility model includes a grate body 1. At both ends of the grate body 1, there are provided ends 4 composed of an upper wing 5 and a lower wing 3. The width L of the end 4 is controlled between 45 and 120 mm. Under the conditions of the same heat load and the impact external force of the sintered cake, the possibility of thermal deformation is greatly reduced, and the problem of rapid burnout speed is delayed, thereby prolonging its service life. The grate body 1 can be at least two, and a ventilation gap 5 of 5-10 mm is formed between adjacent grate bodies 1. The upper wing 5 and the lower wing 3 are in contact with the trolley cross beam 7. Among them, a cavity 15 for heat dissipation is provided at the contact position between the upper wing 5 and the trolley cross beam 7. It also includes a reinforcing rib 14. The reinforcing rib 14 is located inside the cavity 15 and abuts against the inner wall of the cavity 15. A limiting groove 10 is provided on one side of the end 4, and a limiting boss 11 is provided on the other side, which can ensure that during the operation of adjacent grate bars, their relative displacement is controlled within the range of 2-7 mm, ensuring the safe operation of the grate bars.
[0025] The upper surface of the end of the grate bar is provided with an inclined surface 13 of 30-70°. When discharging ore at the tail of the sintering machine, it can reduce the impact force of the sintered cake on it and reduce the problem of grate bar deformation caused by external force impact. When there are two grate bodies 1, they can be divided into grate body one 1-1 and grate body two 1-2. The grate body one 1-1 and the grate body two 1-2 are connected by a male-female cross bridge 12 to form an integral structure. The sub-grate bar 9 and the mother grate bar 8 are of asymmetric structure and the weight of the mother grate bar 8 is greater than that of the sub-grate bar 9. The upper wing 5 and the lower wing 3 can be arranged on the mother grate bar 8 in a vertically symmetric manner and form a rectangular tiger's mouth to clamp on the trolley cross beam 7 and move together with the sintering machine trolley. Since the sub-grate bar 9 is not designed with a lower wing and belongs to an asymmetric structure, when the sintering machine trolley returns, there will be a relative displacement of about 2-7 mm in the Y direction (perpendicular to the upper plane of the grate body) with the mother grate bar 8, which can automatically clean the adhesive (or small-sized bedding material) between adjacent male and female grate bars online, that is, it has self-cleaning property. When the male and female grate bars return to the head of the sintering machine, under the action of the flat pressing roller, they can be reset with the mother grate bar 8 again and neatly clamp on the trolley cross beam to start the repetitive work of the next cycle.
[0026] The above text has generally described the present invention in detail. However, based on the present invention, some modifications or improvements can be made, which are obvious to those of ordinary skill in the technical field. Therefore, the modifications or improvements made without departing from the spirit of the present invention are within the protection scope of the present invention.
Claims
1. An end structure of a grate bar in the middle of a sintering machine trolley, comprising a grate body (1), wherein both ends of the grate body (1) are respectively provided with end portions (4), and a width L of the end portions (4) is not less than 45 mm.
2. The end structure of the grate bars in the middle of the sintering machine trolley according to claim 1, characterized in that: The grate bodies (1) may be at least two, and a wind clearance of 5-10 mm is formed between adjacent grate bodies (1).
3. The end structure of the grate bars in the middle of the sintering machine trolley according to claim 1, characterized in that: The upper wing (5) and the lower wing (3) are in contact with the trolley cross beam (7), wherein a cavity (15) for heat dissipation is provided at the contact position between the upper wing (5) and the trolley cross beam (7).
4. The end structure of the grate bars in the middle of the sintering machine trolley according to claim 3, characterized in that: It also includes a reinforcing rib (14), which is located inside the cavity (15) and abuts against the inner wall of the cavity (15).
5. The end structure of the grate bars in the middle of the sintering machine trolley according to claim 1, characterized in that: A limiting groove (10) is provided on one side of the end portion (4), and a limiting boss (11) is provided on the other side.
6. The end structure of the grate bars in the middle of the sintering machine trolley according to claim 1, characterized in that: The end portion (4) is provided with a 30-70° inclined surface (13).
7. The end structure of the grate bars in the middle of the sintering machine trolley according to claim 2, characterized in that: When there are two grate bodies (1), they can be divided into a grate body 1 (1-1) without a lower wing and a grate body 2 (1-2) with a lower wing, and the grate body 1 (1-1) and the grate body 2 (1-2) are connected via a bridge (12).
8. The end structure of the grate bars in the middle of the sintering machine trolley according to claim 7, characterized in that: The grate body 1 (1-1) and the end portion (4) form a sub-grate bar (9), and the grate body 2 (1-2), the end portion (4) and the lower wing (3) form a main grate bar (8). The sub-grate bar (9) and the main grate bar (8) are of an asymmetric structure, and the weight of the main grate bar (8) is greater than that of the sub-grate bar (9).